For use in Applicant's SDN-D315-12-10-4091 milling cutter shown in FIG. 1, an insert bearing cartridge has a pair of transversely directed side surfaces with an imaginary bisector plane defining a leading cartridge portion with a chip clearance wall and a trailing cartridge portion with an insert receiving pocket. The insert receiving pocket has a pocket base wall which is substantially parallel to its associated side surface.
Due to this conventional design, a cartridge is mounted in a relatively deep and elongated recess formed in a peripheral surface of a milling cutter body such that both its leading and trailing cartridge portions substantially lie wholly radially inward of the peripheral surface whereby it is adequately supported by a support beam and has sufficient chip clearance space. As shown, a recess has a straight trailing surface having a similar dimension as the side surface associated with the trailing cartridge portion which abuts thereagainst. In addition, a recess has a bow shaped leading surface which is considerably longer than the side surface associated with the leading cartridge portion, the leading surface having an inner portion adjacent its associated trailing surface against which the side surface abuts and an outer portion delimiting the necessary chip clearance space.
A disadvantage of the milling cutter of the above type is that the pitch between adjacent cartridges is limited such that a 250 mm diameter milling cutter has 14 effective cutting edges denoted Z=14. Further disadvantages of the milling cutter of the above type are that its relatively costly milling cutter body is poorly protected by cartridges and is insufficiently strong to absorb the cutting forces due to its support beams having a relatively small cross-section at their bases.